Redefining the collateral system between the superior mesenteric artery and inferior mesenteric artery: a novel classification.

AIM: The aim of this study was to evaluate the arterial collateral vasculature between the superior mesenteric artery and the inferior mesenteric artery (IMA) from a surgical perspective. METHOD: A total of 107 fresh adult cadavers (94 male) were studied with emphasis on the vascular anatomy of the left colon. Dissections were carried out mimicking the anterior resection technique. The vasculature of the left mesocolon and the collaterals between the superior mesenteric artery and the IMA with respect to their relationship to the inferior mesenteric vein (IMV) were assessed and classified. Collaterals were classified into three different groups: marginal anastomoses (via the marginal = pericolic artery), intermediate mesocolic anastomoses (parallel to the marginal artery but neither adjacent to the IMV nor close to the duodenum) and central mesocolic anastomoses (next to the IMV at the level of the duodenojejunal junction and the lower border of the pancreas). RESULTS: All patients had a marginal anastomosis. However, the marginal anastomosis, as the only anastomosis between the superior and inferior mesenteric arteries at the splenic flexure, was observed in 41 cases (38%). In addition to the marginal artery, intermediate mesocolic anastomoses were found in 49 (46%) and a central mesocolic anastomosis was observed in 17 (16%) of the 107 cases in the splenic flexure mesocolon. It is in this latter variant that collateral vessels can be compromised during ligation/transection of the IMV. CONCLUSION: This new classification can contribute to a precise mesocolic dissection technique and splenic flexure mobilization and help prevent ischaemic damage to the descending colon.

Measurement of interscalene space volume in diagnosis of thoracic outlet syndrome: a cadaver study

Background/aim: The aim of this study was to measure the volume of interscalene space in thoracic outlet region on cadavers and radiological images and to analyze the potential value of these measurements in diagnosis and treatment of thoracic outlet syndrome (TOS). Materials and methods: The dimensions of the anterior interscalene space in 8 formalin-fixed human cadavers were studied by direct measurement and additionally evaluation of the volume of this space were done by using mold and volume calculation formula of square pyramid, due to resembling a pyramid. In the second phase of this study, interscalene space volume was calculated by formula and compared to calculations from computed tomography (CT) sections in 18 TOS and 16 control patients. Results: There was a strong correlation between the volume calculated by formula (4.79 ± 2.18 cm3) and by mold (4.84 ± 1.58 cm3), (R = 0.934, p = 0.001) in cadavers. The average volume measured in TOS patients (2.05 ± 0.32 cm3) was significantly smaller than control patients (4.30 ± 1.85 cm3, p < 0.0001). There were excellent or good results in 14 patients whereas in 4 patients who had neurogenic TOS achieved fair results after surgery. In these 4 patients the average volumes of abnormal sides were close to the healthy sides. Conclusion: In our study, volume of interscalene space in TOS patients was statistically smaller than control group. Also, the volume was even smaller in patients with excellent or good results after surgery. In this respect, volumetric measurements from CT sections could be used in diagnosis and treatment selection in TOS patients.

Variations in the Vascular Anatomy of the Right Colon and Implications for Right-Sided Colon Surgery.

BACKGROUND: Knowledge of the normal pattern and variations of the blood supply of the right colon is crucial for better outcomes after colon surgery. OBJECTIVE: The purpose of this study was to describe the precise vascular anatomy of the right colon according to surgical perspective. DESIGN: Adult fresh cadavers were dissected between January 2013 and October 2015, focusing on the venous and arterial anatomy of the right side of the colon. SETTINGS: Macroscopic anatomical dissections were performed on 111 adult fresh cadavers with emphasis on the vascular anatomy of the right colon. The colic tributaries of the superior mesenteric artery and vein were documented in writing. Furthermore, the dissections were recorded with a video camera. RESULTS: The incidence of colic arteries arising from the superior mesenteric artery included ileocolic artery, 100%; right colic artery, 33.3%; middle colic artery, 100%; and accessory middle colic artery, 11,7%. All 111 cadavers had a single ileocolic vein, which drained into the superior mesenteric vein in 103 cases (92.8%), into the gastro-pancreatico-colic trunk in 7 cases (6.3%), and into the jejunal trunk in 1 case (0.9%). The drainage site of the ileocolic vein to the superior mesenteric vein varied, and in 9% of cases the ileocolic vein did not accompany the ileocolic artery. The gastro-pancreatico-colic trunk was detected in 87 cases (78.4%); with several forms of the origin of the respective branches, the gastropancreatic trunk was detected in 24 cases (21.6), and the classic gastrocolic trunk of Henle was not detected. Variations were found in the formation and drainage routes of other venous colic tributaries of the superior mesenteric vein. LIMITATIONS: This study is limited by its use of cadavers in that it is impossible to trace each vessel to its origin in live surgery. CONCLUSIONS: Surgeons must watch, observe, and bear in mind that vascular variations can occur. Awareness of these complex variations may improve the quality of surgery and may prevent devastating complications during right-sided colon resections.

Evaluation of Celiac Trunk, Hepatic Artery Variations, and Their Collateral Arteries by Multi-Slice Computed Tomography.

OBJECTIVES: Celiac Trunk (CT) is a vital artery and the first unmatched branch of the abdominal aorta, providing blood to upper abdominal structures, particularly the liver, stomach, and spleen. It is essential to know its anatomy in terms of pancreas, spleen, gallbladder, liver surgeries, and interventional radiological procedures such as chemoembolization. The aim of our study is to contribute to the literature with the measurements of distances between the diaphragmatic crus and vascular structures with their diameters, which have been studied insufficiently, and to detect the possible relationships between vascular variations and collateral branches. METHODS: Imaging findings of 200 patients (114 males and 86 females), who underwent Multi-Section Computed Tomography examination with various indications in our center between June 2016 and July 2020, were retrospectively analyzed. The statistical relations between CT and Hepatic Artery variations, collateral formations, age, and gender were evaluated with the Spearman's Rho Correlation Coefficient Test. RESULTS: The distance between the crus of diaphragm and CT was 4-60 mm (mean 24.3 mm), the distance between CT and superior mesenteric artery (SMA) was 2.5-35 mm (mean 8.6 mm), CT diameter was 4.6-9.4 mm (mean 7.3 mm), and the main hepatic artery diameter was 2.4-5.8 mm (mean 4.1 mm). There was no correlation in our study between CT, Hepatic Artery variations, and their collaterals (r in range of -20,124-0.116, p>0.05). It can be said that in cases of the single accessory left hepatic artery originating from the left gastric artery, such as Michel's Type V and Type VIII, collaterals between common hepatic artery and SMA were relatively more frequent (p=0.1). CONCLUSION: Our study contributed to the literature by measuring the distance between diaphragmatic crus-vascular structures, which has been little studied in the past. Frequencies of CT and Hepatic Artery variations that have been detected in our study are similar to the results of the previous studies with non-malignancy patient groups.

Anatomic Analysis of the Internal and External Aspects of the Pterion.

OBJECTIVE: The pterion is an H-shaped suture complex. This study's goal was to determine the location of its external and internal surfaces and extension and emphasize and discuss its surgical importance. METHODS: Fifty dried adult human skulls were obtained from the Department of Anatomy. A 2-mm drill bit was placed externally over the pterion, and the pterion was drilled through the bone perpendicular to the skull's surface. RESULTS: The midpoint of the H shape in the pterion area was not at the same level on the skull's external and internal pterion surfaces. According to these measurements, the external pterion lay above the internal pterion when the skull was viewed externally. Furthermore, the internal pterion was on average longer than the external pterion. The internal and external pterions were schematized such that the skull was viewed from the outside. These areas were divided into 4 quadrants (anterior-superior, anterior-inferior, posterior-superior, and posterior-inferior) by a vertical and horizontal line. In 30 cases (60%), sulci of the middle meningeal artery's parietal branches entered the posterior-superior quadrant on the bone, whereas the artery's frontal branches were located in the anterior-superior and anterior-inferior quadrants, and the Sylvian fissure's origin was in the posterior-inferior quadrant. CONCLUSIONS: By using a subdivision into 4 quadrants, and considering our anatomic findings, we determined the way surgical procedures can be performed more easily and reliably. Even with modern localization technologies, anatomic landmarks can be useful to the neurosurgeon.